github.com/ottenhoff/terraform@v0.7.0-rc1.0.20160607213102-ac2d195cc560/builtin/providers/aws/resource_aws_autoscaling_group.go (about)

     1  package aws
     2  
     3  import (
     4  	"fmt"
     5  	"log"
     6  	"strings"
     7  	"time"
     8  
     9  	"github.com/hashicorp/terraform/helper/resource"
    10  	"github.com/hashicorp/terraform/helper/schema"
    11  
    12  	"github.com/aws/aws-sdk-go/aws"
    13  	"github.com/aws/aws-sdk-go/aws/awserr"
    14  	"github.com/aws/aws-sdk-go/service/autoscaling"
    15  	"github.com/aws/aws-sdk-go/service/elb"
    16  )
    17  
    18  func resourceAwsAutoscalingGroup() *schema.Resource {
    19  	return &schema.Resource{
    20  		Create: resourceAwsAutoscalingGroupCreate,
    21  		Read:   resourceAwsAutoscalingGroupRead,
    22  		Update: resourceAwsAutoscalingGroupUpdate,
    23  		Delete: resourceAwsAutoscalingGroupDelete,
    24  		Importer: &schema.ResourceImporter{
    25  			State: schema.ImportStatePassthrough,
    26  		},
    27  
    28  		Schema: map[string]*schema.Schema{
    29  			"name": &schema.Schema{
    30  				Type:     schema.TypeString,
    31  				Optional: true,
    32  				Computed: true,
    33  				ForceNew: true,
    34  				ValidateFunc: func(v interface{}, k string) (ws []string, errors []error) {
    35  					// https://github.com/boto/botocore/blob/9f322b1/botocore/data/autoscaling/2011-01-01/service-2.json#L1862-L1873
    36  					value := v.(string)
    37  					if len(value) > 255 {
    38  						errors = append(errors, fmt.Errorf(
    39  							"%q cannot be longer than 255 characters", k))
    40  					}
    41  					return
    42  				},
    43  			},
    44  
    45  			"launch_configuration": &schema.Schema{
    46  				Type:     schema.TypeString,
    47  				Required: true,
    48  			},
    49  
    50  			"desired_capacity": &schema.Schema{
    51  				Type:     schema.TypeInt,
    52  				Optional: true,
    53  				Computed: true,
    54  			},
    55  
    56  			"min_elb_capacity": &schema.Schema{
    57  				Type:     schema.TypeInt,
    58  				Optional: true,
    59  			},
    60  
    61  			"min_size": &schema.Schema{
    62  				Type:     schema.TypeInt,
    63  				Required: true,
    64  			},
    65  
    66  			"max_size": &schema.Schema{
    67  				Type:     schema.TypeInt,
    68  				Required: true,
    69  			},
    70  
    71  			"default_cooldown": &schema.Schema{
    72  				Type:     schema.TypeInt,
    73  				Optional: true,
    74  				Computed: true,
    75  			},
    76  
    77  			"force_delete": &schema.Schema{
    78  				Type:     schema.TypeBool,
    79  				Optional: true,
    80  				Default:  false,
    81  			},
    82  
    83  			"health_check_grace_period": &schema.Schema{
    84  				Type:     schema.TypeInt,
    85  				Optional: true,
    86  				Default:  300,
    87  			},
    88  
    89  			"health_check_type": &schema.Schema{
    90  				Type:     schema.TypeString,
    91  				Optional: true,
    92  				Computed: true,
    93  			},
    94  
    95  			"availability_zones": &schema.Schema{
    96  				Type:     schema.TypeSet,
    97  				Optional: true,
    98  				Computed: true,
    99  				Elem:     &schema.Schema{Type: schema.TypeString},
   100  				Set:      schema.HashString,
   101  			},
   102  
   103  			"placement_group": &schema.Schema{
   104  				Type:     schema.TypeString,
   105  				Optional: true,
   106  			},
   107  
   108  			"load_balancers": &schema.Schema{
   109  				Type:     schema.TypeSet,
   110  				Optional: true,
   111  				Elem:     &schema.Schema{Type: schema.TypeString},
   112  				Set:      schema.HashString,
   113  			},
   114  
   115  			"vpc_zone_identifier": &schema.Schema{
   116  				Type:     schema.TypeSet,
   117  				Optional: true,
   118  				Computed: true,
   119  				Elem:     &schema.Schema{Type: schema.TypeString},
   120  				Set:      schema.HashString,
   121  			},
   122  
   123  			"termination_policies": &schema.Schema{
   124  				Type:     schema.TypeList,
   125  				Optional: true,
   126  				Elem:     &schema.Schema{Type: schema.TypeString},
   127  			},
   128  
   129  			"wait_for_capacity_timeout": &schema.Schema{
   130  				Type:     schema.TypeString,
   131  				Optional: true,
   132  				Default:  "10m",
   133  				ValidateFunc: func(v interface{}, k string) (ws []string, errors []error) {
   134  					value := v.(string)
   135  					duration, err := time.ParseDuration(value)
   136  					if err != nil {
   137  						errors = append(errors, fmt.Errorf(
   138  							"%q cannot be parsed as a duration: %s", k, err))
   139  					}
   140  					if duration < 0 {
   141  						errors = append(errors, fmt.Errorf(
   142  							"%q must be greater than zero", k))
   143  					}
   144  					return
   145  				},
   146  			},
   147  
   148  			"wait_for_elb_capacity": &schema.Schema{
   149  				Type:     schema.TypeInt,
   150  				Optional: true,
   151  			},
   152  
   153  			"enabled_metrics": &schema.Schema{
   154  				Type:     schema.TypeSet,
   155  				Optional: true,
   156  				Elem:     &schema.Schema{Type: schema.TypeString},
   157  				Set:      schema.HashString,
   158  			},
   159  
   160  			"metrics_granularity": &schema.Schema{
   161  				Type:     schema.TypeString,
   162  				Optional: true,
   163  				Default:  "1Minute",
   164  			},
   165  
   166  			"tag": autoscalingTagsSchema(),
   167  		},
   168  	}
   169  }
   170  
   171  func resourceAwsAutoscalingGroupCreate(d *schema.ResourceData, meta interface{}) error {
   172  	conn := meta.(*AWSClient).autoscalingconn
   173  
   174  	var autoScalingGroupOpts autoscaling.CreateAutoScalingGroupInput
   175  
   176  	var asgName string
   177  	if v, ok := d.GetOk("name"); ok {
   178  		asgName = v.(string)
   179  	} else {
   180  		asgName = resource.PrefixedUniqueId("tf-asg-")
   181  		d.Set("name", asgName)
   182  	}
   183  
   184  	autoScalingGroupOpts.AutoScalingGroupName = aws.String(asgName)
   185  	autoScalingGroupOpts.LaunchConfigurationName = aws.String(d.Get("launch_configuration").(string))
   186  	autoScalingGroupOpts.MinSize = aws.Int64(int64(d.Get("min_size").(int)))
   187  	autoScalingGroupOpts.MaxSize = aws.Int64(int64(d.Get("max_size").(int)))
   188  
   189  	// Availability Zones are optional if VPC Zone Identifer(s) are specified
   190  	if v, ok := d.GetOk("availability_zones"); ok && v.(*schema.Set).Len() > 0 {
   191  		autoScalingGroupOpts.AvailabilityZones = expandStringList(v.(*schema.Set).List())
   192  	}
   193  
   194  	if v, ok := d.GetOk("tag"); ok {
   195  		autoScalingGroupOpts.Tags = autoscalingTagsFromMap(
   196  			setToMapByKey(v.(*schema.Set), "key"), d.Get("name").(string))
   197  	}
   198  
   199  	if v, ok := d.GetOk("default_cooldown"); ok {
   200  		autoScalingGroupOpts.DefaultCooldown = aws.Int64(int64(v.(int)))
   201  	}
   202  
   203  	if v, ok := d.GetOk("health_check_type"); ok && v.(string) != "" {
   204  		autoScalingGroupOpts.HealthCheckType = aws.String(v.(string))
   205  	}
   206  
   207  	if v, ok := d.GetOk("desired_capacity"); ok {
   208  		autoScalingGroupOpts.DesiredCapacity = aws.Int64(int64(v.(int)))
   209  	}
   210  
   211  	if v, ok := d.GetOk("health_check_grace_period"); ok {
   212  		autoScalingGroupOpts.HealthCheckGracePeriod = aws.Int64(int64(v.(int)))
   213  	}
   214  
   215  	if v, ok := d.GetOk("placement_group"); ok {
   216  		autoScalingGroupOpts.PlacementGroup = aws.String(v.(string))
   217  	}
   218  
   219  	if v, ok := d.GetOk("load_balancers"); ok && v.(*schema.Set).Len() > 0 {
   220  		autoScalingGroupOpts.LoadBalancerNames = expandStringList(
   221  			v.(*schema.Set).List())
   222  	}
   223  
   224  	if v, ok := d.GetOk("vpc_zone_identifier"); ok && v.(*schema.Set).Len() > 0 {
   225  		autoScalingGroupOpts.VPCZoneIdentifier = expandVpcZoneIdentifiers(v.(*schema.Set).List())
   226  	}
   227  
   228  	if v, ok := d.GetOk("termination_policies"); ok && len(v.([]interface{})) > 0 {
   229  		autoScalingGroupOpts.TerminationPolicies = expandStringList(v.([]interface{}))
   230  	}
   231  
   232  	log.Printf("[DEBUG] AutoScaling Group create configuration: %#v", autoScalingGroupOpts)
   233  	_, err := conn.CreateAutoScalingGroup(&autoScalingGroupOpts)
   234  	if err != nil {
   235  		return fmt.Errorf("Error creating Autoscaling Group: %s", err)
   236  	}
   237  
   238  	d.SetId(d.Get("name").(string))
   239  	log.Printf("[INFO] AutoScaling Group ID: %s", d.Id())
   240  
   241  	if err := waitForASGCapacity(d, meta, capacitySatifiedCreate); err != nil {
   242  		return err
   243  	}
   244  
   245  	if _, ok := d.GetOk("enabled_metrics"); ok {
   246  		metricsErr := enableASGMetricsCollection(d, conn)
   247  		if metricsErr != nil {
   248  			return metricsErr
   249  		}
   250  	}
   251  
   252  	return resourceAwsAutoscalingGroupRead(d, meta)
   253  }
   254  
   255  func resourceAwsAutoscalingGroupRead(d *schema.ResourceData, meta interface{}) error {
   256  	conn := meta.(*AWSClient).autoscalingconn
   257  
   258  	g, err := getAwsAutoscalingGroup(d.Id(), conn)
   259  	if err != nil {
   260  		return err
   261  	}
   262  	if g == nil {
   263  		log.Printf("[INFO] Autoscaling Group %q not found", d.Id())
   264  		d.SetId("")
   265  		return nil
   266  	}
   267  
   268  	d.Set("availability_zones", flattenStringList(g.AvailabilityZones))
   269  	d.Set("default_cooldown", g.DefaultCooldown)
   270  	d.Set("desired_capacity", g.DesiredCapacity)
   271  	d.Set("health_check_grace_period", g.HealthCheckGracePeriod)
   272  	d.Set("health_check_type", g.HealthCheckType)
   273  	d.Set("launch_configuration", g.LaunchConfigurationName)
   274  	d.Set("load_balancers", flattenStringList(g.LoadBalancerNames))
   275  	d.Set("min_size", g.MinSize)
   276  	d.Set("max_size", g.MaxSize)
   277  	d.Set("placement_group", g.PlacementGroup)
   278  	d.Set("name", g.AutoScalingGroupName)
   279  	d.Set("tag", autoscalingTagDescriptionsToSlice(g.Tags))
   280  	d.Set("vpc_zone_identifier", strings.Split(*g.VPCZoneIdentifier, ","))
   281  
   282  	// If no termination polices are explicitly configured and the upstream state
   283  	// is only using the "Default" policy, clear the state to make it consistent
   284  	// with the default AWS create API behavior.
   285  	_, ok := d.GetOk("termination_policies")
   286  	if !ok && len(g.TerminationPolicies) == 1 && *g.TerminationPolicies[0] == "Default" {
   287  		d.Set("termination_policies", []interface{}{})
   288  	} else {
   289  		d.Set("termination_policies", flattenStringList(g.TerminationPolicies))
   290  	}
   291  
   292  	if g.EnabledMetrics != nil {
   293  		if err := d.Set("enabled_metrics", flattenAsgEnabledMetrics(g.EnabledMetrics)); err != nil {
   294  			log.Printf("[WARN] Error setting metrics for (%s): %s", d.Id(), err)
   295  		}
   296  		d.Set("metrics_granularity", g.EnabledMetrics[0].Granularity)
   297  	}
   298  
   299  	return nil
   300  }
   301  
   302  func resourceAwsAutoscalingGroupUpdate(d *schema.ResourceData, meta interface{}) error {
   303  	conn := meta.(*AWSClient).autoscalingconn
   304  	shouldWaitForCapacity := false
   305  
   306  	opts := autoscaling.UpdateAutoScalingGroupInput{
   307  		AutoScalingGroupName: aws.String(d.Id()),
   308  	}
   309  
   310  	if d.HasChange("default_cooldown") {
   311  		opts.DefaultCooldown = aws.Int64(int64(d.Get("default_cooldown").(int)))
   312  	}
   313  
   314  	if d.HasChange("desired_capacity") {
   315  		opts.DesiredCapacity = aws.Int64(int64(d.Get("desired_capacity").(int)))
   316  		shouldWaitForCapacity = true
   317  	}
   318  
   319  	if d.HasChange("launch_configuration") {
   320  		opts.LaunchConfigurationName = aws.String(d.Get("launch_configuration").(string))
   321  	}
   322  
   323  	if d.HasChange("min_size") {
   324  		opts.MinSize = aws.Int64(int64(d.Get("min_size").(int)))
   325  		shouldWaitForCapacity = true
   326  	}
   327  
   328  	if d.HasChange("max_size") {
   329  		opts.MaxSize = aws.Int64(int64(d.Get("max_size").(int)))
   330  	}
   331  
   332  	if d.HasChange("health_check_grace_period") {
   333  		opts.HealthCheckGracePeriod = aws.Int64(int64(d.Get("health_check_grace_period").(int)))
   334  	}
   335  
   336  	if d.HasChange("health_check_type") {
   337  		opts.HealthCheckGracePeriod = aws.Int64(int64(d.Get("health_check_grace_period").(int)))
   338  		opts.HealthCheckType = aws.String(d.Get("health_check_type").(string))
   339  	}
   340  
   341  	if d.HasChange("vpc_zone_identifier") {
   342  		opts.VPCZoneIdentifier = expandVpcZoneIdentifiers(d.Get("vpc_zone_identifier").(*schema.Set).List())
   343  	}
   344  
   345  	if d.HasChange("availability_zones") {
   346  		if v, ok := d.GetOk("availability_zones"); ok && v.(*schema.Set).Len() > 0 {
   347  			opts.AvailabilityZones = expandStringList(v.(*schema.Set).List())
   348  		}
   349  	}
   350  
   351  	if d.HasChange("placement_group") {
   352  		opts.PlacementGroup = aws.String(d.Get("placement_group").(string))
   353  	}
   354  
   355  	if d.HasChange("termination_policies") {
   356  		// If the termination policy is set to null, we need to explicitly set
   357  		// it back to "Default", or the API won't reset it for us.
   358  		if v, ok := d.GetOk("termination_policies"); ok && len(v.([]interface{})) > 0 {
   359  			opts.TerminationPolicies = expandStringList(v.([]interface{}))
   360  		} else {
   361  			log.Printf("[DEBUG] Explictly setting null termination policy to 'Default'")
   362  			opts.TerminationPolicies = aws.StringSlice([]string{"Default"})
   363  		}
   364  	}
   365  
   366  	if err := setAutoscalingTags(conn, d); err != nil {
   367  		return err
   368  	} else {
   369  		d.SetPartial("tag")
   370  	}
   371  
   372  	log.Printf("[DEBUG] AutoScaling Group update configuration: %#v", opts)
   373  	_, err := conn.UpdateAutoScalingGroup(&opts)
   374  	if err != nil {
   375  		d.Partial(true)
   376  		return fmt.Errorf("Error updating Autoscaling group: %s", err)
   377  	}
   378  
   379  	if d.HasChange("load_balancers") {
   380  
   381  		o, n := d.GetChange("load_balancers")
   382  		if o == nil {
   383  			o = new(schema.Set)
   384  		}
   385  		if n == nil {
   386  			n = new(schema.Set)
   387  		}
   388  
   389  		os := o.(*schema.Set)
   390  		ns := n.(*schema.Set)
   391  		remove := expandStringList(os.Difference(ns).List())
   392  		add := expandStringList(ns.Difference(os).List())
   393  
   394  		if len(remove) > 0 {
   395  			_, err := conn.DetachLoadBalancers(&autoscaling.DetachLoadBalancersInput{
   396  				AutoScalingGroupName: aws.String(d.Id()),
   397  				LoadBalancerNames:    remove,
   398  			})
   399  			if err != nil {
   400  				return fmt.Errorf("[WARN] Error updating Load Balancers for AutoScaling Group (%s), error: %s", d.Id(), err)
   401  			}
   402  		}
   403  
   404  		if len(add) > 0 {
   405  			_, err := conn.AttachLoadBalancers(&autoscaling.AttachLoadBalancersInput{
   406  				AutoScalingGroupName: aws.String(d.Id()),
   407  				LoadBalancerNames:    add,
   408  			})
   409  			if err != nil {
   410  				return fmt.Errorf("[WARN] Error updating Load Balancers for AutoScaling Group (%s), error: %s", d.Id(), err)
   411  			}
   412  		}
   413  	}
   414  
   415  	if shouldWaitForCapacity {
   416  		waitForASGCapacity(d, meta, capacitySatifiedUpdate)
   417  	}
   418  
   419  	if d.HasChange("enabled_metrics") {
   420  		updateASGMetricsCollection(d, conn)
   421  	}
   422  
   423  	return resourceAwsAutoscalingGroupRead(d, meta)
   424  }
   425  
   426  func resourceAwsAutoscalingGroupDelete(d *schema.ResourceData, meta interface{}) error {
   427  	conn := meta.(*AWSClient).autoscalingconn
   428  
   429  	// Read the autoscaling group first. If it doesn't exist, we're done.
   430  	// We need the group in order to check if there are instances attached.
   431  	// If so, we need to remove those first.
   432  	g, err := getAwsAutoscalingGroup(d.Id(), conn)
   433  	if err != nil {
   434  		return err
   435  	}
   436  	if g == nil {
   437  		log.Printf("[INFO] Autoscaling Group %q not found", d.Id())
   438  		d.SetId("")
   439  		return nil
   440  	}
   441  	if len(g.Instances) > 0 || *g.DesiredCapacity > 0 {
   442  		if err := resourceAwsAutoscalingGroupDrain(d, meta); err != nil {
   443  			return err
   444  		}
   445  	}
   446  
   447  	log.Printf("[DEBUG] AutoScaling Group destroy: %v", d.Id())
   448  	deleteopts := autoscaling.DeleteAutoScalingGroupInput{
   449  		AutoScalingGroupName: aws.String(d.Id()),
   450  		ForceDelete:          aws.Bool(d.Get("force_delete").(bool)),
   451  	}
   452  
   453  	// We retry the delete operation to handle InUse/InProgress errors coming
   454  	// from scaling operations. We should be able to sneak in a delete in between
   455  	// scaling operations within 5m.
   456  	err = resource.Retry(5*time.Minute, func() *resource.RetryError {
   457  		if _, err := conn.DeleteAutoScalingGroup(&deleteopts); err != nil {
   458  			if awserr, ok := err.(awserr.Error); ok {
   459  				switch awserr.Code() {
   460  				case "InvalidGroup.NotFound":
   461  					// Already gone? Sure!
   462  					return nil
   463  				case "ResourceInUse", "ScalingActivityInProgress":
   464  					// These are retryable
   465  					return resource.RetryableError(awserr)
   466  				}
   467  			}
   468  			// Didn't recognize the error, so shouldn't retry.
   469  			return resource.NonRetryableError(err)
   470  		}
   471  		// Successful delete
   472  		return nil
   473  	})
   474  	if err != nil {
   475  		return err
   476  	}
   477  
   478  	return resource.Retry(5*time.Minute, func() *resource.RetryError {
   479  		if g, _ = getAwsAutoscalingGroup(d.Id(), conn); g != nil {
   480  			return resource.RetryableError(
   481  				fmt.Errorf("Auto Scaling Group still exists"))
   482  		}
   483  		return nil
   484  	})
   485  }
   486  
   487  func getAwsAutoscalingGroup(
   488  	asgName string,
   489  	conn *autoscaling.AutoScaling) (*autoscaling.Group, error) {
   490  
   491  	describeOpts := autoscaling.DescribeAutoScalingGroupsInput{
   492  		AutoScalingGroupNames: []*string{aws.String(asgName)},
   493  	}
   494  
   495  	log.Printf("[DEBUG] AutoScaling Group describe configuration: %#v", describeOpts)
   496  	describeGroups, err := conn.DescribeAutoScalingGroups(&describeOpts)
   497  	if err != nil {
   498  		autoscalingerr, ok := err.(awserr.Error)
   499  		if ok && autoscalingerr.Code() == "InvalidGroup.NotFound" {
   500  			return nil, nil
   501  		}
   502  
   503  		return nil, fmt.Errorf("Error retrieving AutoScaling groups: %s", err)
   504  	}
   505  
   506  	// Search for the autoscaling group
   507  	for idx, asc := range describeGroups.AutoScalingGroups {
   508  		if *asc.AutoScalingGroupName == asgName {
   509  			return describeGroups.AutoScalingGroups[idx], nil
   510  		}
   511  	}
   512  
   513  	return nil, nil
   514  }
   515  
   516  func resourceAwsAutoscalingGroupDrain(d *schema.ResourceData, meta interface{}) error {
   517  	conn := meta.(*AWSClient).autoscalingconn
   518  
   519  	if d.Get("force_delete").(bool) {
   520  		log.Printf("[DEBUG] Skipping ASG drain, force_delete was set.")
   521  		return nil
   522  	}
   523  
   524  	// First, set the capacity to zero so the group will drain
   525  	log.Printf("[DEBUG] Reducing autoscaling group capacity to zero")
   526  	opts := autoscaling.UpdateAutoScalingGroupInput{
   527  		AutoScalingGroupName: aws.String(d.Id()),
   528  		DesiredCapacity:      aws.Int64(0),
   529  		MinSize:              aws.Int64(0),
   530  		MaxSize:              aws.Int64(0),
   531  	}
   532  	if _, err := conn.UpdateAutoScalingGroup(&opts); err != nil {
   533  		return fmt.Errorf("Error setting capacity to zero to drain: %s", err)
   534  	}
   535  
   536  	// Next, wait for the autoscale group to drain
   537  	log.Printf("[DEBUG] Waiting for group to have zero instances")
   538  	return resource.Retry(10*time.Minute, func() *resource.RetryError {
   539  		g, err := getAwsAutoscalingGroup(d.Id(), conn)
   540  		if err != nil {
   541  			return resource.NonRetryableError(err)
   542  		}
   543  		if g == nil {
   544  			log.Printf("[INFO] Autoscaling Group %q not found", d.Id())
   545  			d.SetId("")
   546  			return nil
   547  		}
   548  
   549  		if len(g.Instances) == 0 {
   550  			return nil
   551  		}
   552  
   553  		return resource.RetryableError(
   554  			fmt.Errorf("group still has %d instances", len(g.Instances)))
   555  	})
   556  }
   557  
   558  func enableASGMetricsCollection(d *schema.ResourceData, conn *autoscaling.AutoScaling) error {
   559  	props := &autoscaling.EnableMetricsCollectionInput{
   560  		AutoScalingGroupName: aws.String(d.Id()),
   561  		Granularity:          aws.String(d.Get("metrics_granularity").(string)),
   562  		Metrics:              expandStringList(d.Get("enabled_metrics").(*schema.Set).List()),
   563  	}
   564  
   565  	log.Printf("[INFO] Enabling metrics collection for the ASG: %s", d.Id())
   566  	_, metricsErr := conn.EnableMetricsCollection(props)
   567  	if metricsErr != nil {
   568  		return metricsErr
   569  	}
   570  
   571  	return nil
   572  }
   573  
   574  func updateASGMetricsCollection(d *schema.ResourceData, conn *autoscaling.AutoScaling) error {
   575  
   576  	o, n := d.GetChange("enabled_metrics")
   577  	if o == nil {
   578  		o = new(schema.Set)
   579  	}
   580  	if n == nil {
   581  		n = new(schema.Set)
   582  	}
   583  
   584  	os := o.(*schema.Set)
   585  	ns := n.(*schema.Set)
   586  
   587  	disableMetrics := os.Difference(ns)
   588  	if disableMetrics.Len() != 0 {
   589  		props := &autoscaling.DisableMetricsCollectionInput{
   590  			AutoScalingGroupName: aws.String(d.Id()),
   591  			Metrics:              expandStringList(disableMetrics.List()),
   592  		}
   593  
   594  		_, err := conn.DisableMetricsCollection(props)
   595  		if err != nil {
   596  			return fmt.Errorf("Failure to Disable metrics collection types for ASG %s: %s", d.Id(), err)
   597  		}
   598  	}
   599  
   600  	enabledMetrics := ns.Difference(os)
   601  	if enabledMetrics.Len() != 0 {
   602  		props := &autoscaling.EnableMetricsCollectionInput{
   603  			AutoScalingGroupName: aws.String(d.Id()),
   604  			Metrics:              expandStringList(enabledMetrics.List()),
   605  		}
   606  
   607  		_, err := conn.EnableMetricsCollection(props)
   608  		if err != nil {
   609  			return fmt.Errorf("Failure to Enable metrics collection types for ASG %s: %s", d.Id(), err)
   610  		}
   611  	}
   612  
   613  	return nil
   614  }
   615  
   616  // Returns a mapping of the instance states of all the ELBs attached to the
   617  // provided ASG.
   618  //
   619  // Nested like: lbName -> instanceId -> instanceState
   620  func getLBInstanceStates(g *autoscaling.Group, meta interface{}) (map[string]map[string]string, error) {
   621  	lbInstanceStates := make(map[string]map[string]string)
   622  	elbconn := meta.(*AWSClient).elbconn
   623  
   624  	for _, lbName := range g.LoadBalancerNames {
   625  		lbInstanceStates[*lbName] = make(map[string]string)
   626  		opts := &elb.DescribeInstanceHealthInput{LoadBalancerName: lbName}
   627  		r, err := elbconn.DescribeInstanceHealth(opts)
   628  		if err != nil {
   629  			return nil, err
   630  		}
   631  		for _, is := range r.InstanceStates {
   632  			if is.InstanceId == nil || is.State == nil {
   633  				continue
   634  			}
   635  			lbInstanceStates[*lbName][*is.InstanceId] = *is.State
   636  		}
   637  	}
   638  
   639  	return lbInstanceStates, nil
   640  }
   641  
   642  func expandVpcZoneIdentifiers(list []interface{}) *string {
   643  	strs := make([]string, len(list))
   644  	for _, s := range list {
   645  		strs = append(strs, s.(string))
   646  	}
   647  	return aws.String(strings.Join(strs, ","))
   648  }